1. Field of the Invention
This invention relates to a drive system and more particularly to a drive arrangement for sensing, through resistive torque, the presence of washing fluid in the cavity of a rotary positive displacement pump.
2. Description of the Prior Art
The prior art shows a continuing search for a system that senses the tub water level and provides a means of lowering the level prior to a period of high speed extraction. Previous work in the appliance field shows systems that disclose electrical or pressure systems for sensing this water level. These systems are used in conjunction with slip clutches or solenoid actuated clutches which are energized, when the water level is reduced to a predetermined level, to activate the extractor. Also shown in prior art is a system that uses a pump for both drain and agitation. In this prior art pump system, a slip clutch is arranged so that the fabric basket will gradually come up to extraction speed as the fluid level in the tub is lowered by pumping out.